1. Technical Field
The present invention relates to a resonator element, a resonator, an oscillator, an electronic apparatus, and a moving object.
2. Related Art
In the past, there has been known a quartz crystal oscillator having a resonator element housed in a package (see, e.g., JP-A-2002-141770 (Document 1)).
The resonator of Document 1 has a base section, a pair of vibrating arms each having a widened portion disposed in one end portion, a resonator element disposed between the pair of vibrating arms, and having a support arm extending from the base section, and a package housing the resonator element. Further, the resonator element is fixed to the package via a pair of electrically-conductive adhesives. The pair of electrically-conductive adhesives are disposed on one surface of the support arm in the thickness direction. According to such a configuration as described above, the resonator can be made relatively small.
However, according to the resonator of Document 1, the resonant frequency in the X-common mode in which the pair of vibrating arms flexurally vibrating in roughly the same in-plane directions in a plan view approximates to the resonant frequency in the main mode in which the pair of vibrating arms repeat getting closer to and getting away from each other to flexurally vibrate roughly in plane, and thus, the X-common mode is combined with the main mode, and a vibration mode mixed with the vibration mode of the X-common mode appears when driving the resonator in the main mode. Although in the tuning-fork resonator element, there is adopted a structure in which the vibration leakage in the main mode becomes as small as possible in the support section, the vibration leakage with respect to the vibration mode of the X-common mode is not suppressed. Therefore, in the resonator of Document 1, the vibration leakage increases when vibrating in the main mode, and thus, the deterioration of the Q value and the deterioration of the CI value due to the deterioration of the Q value are caused problematically.
The resonator element described in JP-A-49-98219 (Document 2) is provided with a constricted part with a decreased width formed in the support arm near to the base section in addition to the features of the resonator element described in Document 1, and can therefore decrease the degree of the approximation of the resonant frequency in the X-common mode to the resonant frequency in the main mode. It should be noted that in such a resonator element as described above, the resonator element is attached to the package in the portions located on the tip side (on the opposite side to the base section) of the constricted part via the pair of electrically-conductive adhesives.
However, in the miniaturization, it is insufficient to reduce the degree of the approximation of the resonant frequency in the X-common mode to the resonant frequency in the main mode.